Questions

Online marketing is the exchange of products and services between the buyers and sellers on the internet.It is also known as e-marketing or internet marketing or online advertising. It may take the form of : 

a.B2C where the products are sold directly to the customers. 

b.B2B where trading networks or auction sites maybe used to reach out to the new customers and serve the existing one

c.C2C where one customer may further sell the product to another customer.

Examples of online marketing may include banner ads, blogs, social network advertisement.

Hence, the missing number iss 25.

A conjugate acid, is a species formed by the reception of a proton (H+) by a base—in other words, it is a base with a hydrogen ion added to it.

On the other hand, a conjugate base is what is left over after an acid has donated a proton during a chemical reaction. Hence, a conjugate base is a species formed by the removal of a proton from an acid.

Because some acids are capable of releasing multiple protons, the conjugate base of an acid may itself be acidic.

Represented as the following chemical reaction:

Acid + Base ⇌ Conjugate Base + Conjugate Acid

The water molecule is the conjugate acid of the hydroxide ion after the latter received the hydrogen proton donated by ammonium. On the other hand, ammonia is the conjugate base for the acid ammonium after ammonium has donated a hydrogen ion towards the production of the water molecule. We can also refer to OH- as a conjugate base of H2O, since the water molecule donates a proton towards the production of NH+4 in the reverse reaction, which is the predominating process in nature due to the strength of the base NH3 over the hydroxide ion.